1. Field of the Invention
This invention relates to machine head assemblies for floor care machines and to a novel torque-transmitting member for use in such machines.
2. Prior Art
Recent developments in floor polishing and scrubbing machines has produced a so-called high-speed floor polishing/scrubbing machine which has been found to clean and polish floors much faster and more efficiently than the conventional lower speed machine. The high speed machines operate at about 350 revolutions per minute as compared to half this amount for the more conventional machines. It has been found that, unfortunately, the higher speed machines are much more difficult to control, thus leading to premature operator fatigue. This control difficulty is thought to be produced by floor discontinuities and for other reasons which cause stress at the machine head which is transmitted to the machine's handle.
Various flexible torque-transmitting devices have been proposed for incorporating into such machines to inhibit such stress transfer but these have generally been found to be ineffective. The simplest and most common torque-transmitting member is a flexible annulus, looking much like a very large washer, which is fastened within the machine head assembly. Such a device has been found to be too expensive to use because it requires a complex fastening arrangement, having many parts.